drm/i915: Account for space on the ring buffer consumed whilst wrapping.

If we fill the tail of the physical ring buffer with NOOP when wrapping,
we need to account for the reduction in available space.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index a3cac5791d76272b21128399979658e0fe69d3bc..26362f8495a8791ed8d0d75657faa4b6c1af346e 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -687,6 +687,7 @@ int intel_wrap_ring_buffer(struct drm_device *dev,
                *virt++ = MI_NOOP;
 
        ring->tail = 0;
+       ring->space = ring->head - 8;
 
        return 0;
 }